2. The Gujarat Coast

This is the second largest oil producing area of the country. Its main oilfields are in Ankleshwar, Cambay-Luni area and Ahmadabad-Kalol region.

(i) Ankleshwar Situated in the district of Bharauch, it stretches over an area of about 30 sq km. The oil of this region belongs to the Eocene period. Oil production in this region was started in 1961. Ankleshwar oil is rich in gasoline and kerosene. The crude oil from this region is sent to the Koyali petroleum refinery.

(ii) Cambay-Luni Region This oilfield lies about 60 km to the west of Vadodara. The drilling operations in this region were started in 1958. The estimated reserves of crude-oil are over 30 million tonnes. The oil of this region is very light with a sulphur content of less than 0.1 per cent. (m) The Ahmadabad-Kalol Region This crude-oil region lies to the north of Gulf of Khambat (Cambay) around the city of Ahmadabad and extends up to Mehsana. Kalol, situated about 25 km to the north of Ahmadabad is an important oilfield of the region. Oil production from this region was started in 1961. Crude oil from this region is supplied mainly to the Koyali refinery.

3. The Brahmaputra Valley As stated above, crude oil was first discovered in the Brahmaputra valley. The oil-bearing rocks spread from the Dehang Basin up to the Surma valley. The main oil producing wells, however, lie in the Dibrugarh and Sibsagar districts of Upper Assam. Some of the important oil producing centres of this region are given below:

(i) The Digboi Oilfield Stretching over an area of about 15 sq km, the Digboi oilfield is one of the oldest oil-fields of the country. The oil of this region belongs to the Eocene and Miocene periods. There are 85 oil wells in this region. Most of the oil is sent to the refinery of Digboi. Since 1959, the Digboi oilfields are worked by the Oil India Limited (OIL).

(ii) The Naharkaliya Oilfield This oil-field lies about 35 km to the south-west of Digboi. Oil production from the Nahaikatiya oilfields was started in 195 1. Crude oil from this region is supplied to the refineries of Noonamati, New Bongaigaon (Assam), and Barauni (Bihar).

4. The Eastern Coast Oil-fields Petroleum and natural gas have been discovered in marine della regions of Mahanadi, Godavari, Krishna, and Kaveri rivers. The Rawa field in the Godavari-Krishna offshore is expected to produce about 3 million tonnes of crude-oil annually. Petroleum has also been discovered in the Kaveri delta.

In addition to these, crude oil has been discovered in the Bilaspur Tehsil of Rampur District of Uttar Pradesh, Jaw'alamukhi area of Punjab, and in the Barmer District of Rajasthan. There are strong possibilities of petroleum and natural gas deposits to be found on the offshore of Andaman and Nicobar, Gulf of Mannar,

Baleshwar coast, Punjab, Haryana and Uttar Pradesh.

The Ministry of Petroleum and Natural Gas is entrusted with the responsibility of exploration and production of oil and natural gas including import of Liquefied Natural Gas (LNG), refining, marketing, distribution import, export and conservation of petroleum products.

Oil and Natural Gas Corporation Limited (ONGC) and Oil India Limited (OIL), the two national companies (NOCs), and private and joint venture companies are engaged in the Exploration and Production of oil and natural gas in the country. Crude oil production during 2005-06 was 32190 MMT by ONGC, OIL, and Private/Joint Venture companies.

The natural gas production during the year 2005-06 was 32.20 Billion Cubic Metres (BCM) from ONGC, OIL and Private/Joint Venture Companies.